1
0
mirror of https://github.com/golang/go synced 2024-10-03 05:21:22 -06:00
go/src/pkg/net/port.go
Russ Cox 41f93a430f net: drop laddr from Dial, cname from LookupHost; new functions
Drop laddr argument from Dial.

Drop cname return from LookupHost.

Add LookupIP, LookupCNAME, ParseCIDR, IP.Equal.
Export SplitHostPort, JoinHostPort.
Add AAAA (IPv6) support to host lookups.

Preparations for implementing some of the
lookups using cgo.

ParseCIDR and IP.Equal are logically new in this CL
but accidentally snuck into an earlier CL about unused
labels that was in the same client.

In crypto/tls, drop laddr from Dial to match net.

R=golang-dev, dsymonds, adg, rh
CC=golang-dev
https://golang.org/cl/4244055
2011-03-28 23:28:42 -04:00

71 lines
1.5 KiB
Go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Read system port mappings from /etc/services
package net
import (
"os"
"sync"
)
var services map[string]map[string]int
var servicesError os.Error
var onceReadServices sync.Once
func readServices() {
services = make(map[string]map[string]int)
var file *file
if file, servicesError = open("/etc/services"); servicesError != nil {
return
}
for line, ok := file.readLine(); ok; line, ok = file.readLine() {
// "http 80/tcp www www-http # World Wide Web HTTP"
if i := byteIndex(line, '#'); i >= 0 {
line = line[0:i]
}
f := getFields(line)
if len(f) < 2 {
continue
}
portnet := f[1] // "tcp/80"
port, j, ok := dtoi(portnet, 0)
if !ok || port <= 0 || j >= len(portnet) || portnet[j] != '/' {
continue
}
netw := portnet[j+1:] // "tcp"
m, ok1 := services[netw]
if !ok1 {
m = make(map[string]int)
services[netw] = m
}
for i := 0; i < len(f); i++ {
if i != 1 { // f[1] was port/net
m[f[i]] = port
}
}
}
file.close()
}
// goLookupPort is the native Go implementation of LookupPort.
func goLookupPort(network, service string) (port int, err os.Error) {
onceReadServices.Do(readServices)
switch network {
case "tcp4", "tcp6":
network = "tcp"
case "udp4", "udp6":
network = "udp"
}
if m, ok := services[network]; ok {
if port, ok = m[service]; ok {
return
}
}
return 0, &AddrError{"unknown port", network + "/" + service}
}